Then, however, they would be accountable for how many times AI fails.

If I'm paying a flat rate, the only economic cost I am worrying about is "will this be faster than me doing it myself if it fails once or twice?"

If I am paying per token, and it goes off for 20 minutes without solving the problem, I've just spent $$ for no result. Why would I even bother using it?

For something like Claude Code, that's an even more concerning issue - how many background tasks have to fail before I reach my monthly spending limit? How do I get granular control to say "only spend 7 dollars on this task - stop if you cannot succeed." - and I have to write my own accounting system for whether it succeeds or fails.